title: Relationship between retinal layer thickness and focal macular electroretinogram components after epiretinal membrane surgery.
abstract: OBJECTIVE
  To study the effect of epiretinal membrane (ERM) removal on the function and structure of the retina, and to determine whether the functional changes were correlated with the changes in the thickness of different retinal layers.
  
  
  METHODS
  Focal macular electroretinography (FMERG) and spectral-domain optical coherence tomography (SD-OCT) were performed on 17 eyes of 15 patients before and after ERM surgery. The parafoveal retina was divided into an inner layer, a middle layer, and an outer layer in the OCT images. The thickness of each layer was measured before and after the ERM surgery. The a-wave, b-wave, and oscillatory potentials (OPs) of the FMERGs were analyzed before and after the ERM surgery.
  
  
  RESULTS
  The thickness of the inner and middle retinal layers was significantly reduced after surgery (by 39% and 23%, respectively). The mean amplitudes of the b-waves and OPs at 6 months postoperatively were significantly larger than those recorded preoperatively (by 21% and 61%, respectively). The ratios of the pre- to postoperative b-wave and OP amplitudes were correlated with the thickness reduction of the middle retinal layer (b-wave, r = -0.51, P < 0.05; OPs, r = -0.82, P < 0.01).
  
  
  CONCLUSIONS
  The significant correlations between the reduction in the thickness of the middle retinal layer and increase in the amplitude of the b-waves and OPs suggest that the improvement of macular function after ERM peeling is due to the decrease in the thickness of the middle retinal layer.
authors.affiliation: Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Hibi
authors.forename: Shinji
authors.initials: S
authors.lastname: Ueno
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Ito
authors.forename: Chang-Hua
authors.initials: CH
authors.lastname: Piao
authors.forename: Mineo
authors.initials: M
authors.lastname: Kondo
authors.forename: Hiroko
authors.initials: H
authors.lastname: Terasaki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D004596:Electroretinography / Q000379:methods; D019773:Epiretinal Membrane / Q000601:surgery*; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000473:pathology / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012160:Retina / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D012846:Singapore; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology
keywords: focal macular electroretinograms; idiopathic epiretinal membrane; optical coherence tomography